Volume 6, Issue 1, March 2020, Page: 39-49
A National Scale Assessment of Temporal Variations in Groundwater Discharge to Rivers: Malawi
Laura Kelly, Department of Civil and Environmental Engineering, University of Strathclyde, Glasgow, UK
Douglas Bertram, Department of Civil and Environmental Engineering, University of Strathclyde, Glasgow, UK
Robert Kalin, Department of Civil and Environmental Engineering, University of Strathclyde, Glasgow, UK
Cosmo Ngongondo, Department of Geography and Earth Sciences, University of Malawi ‘Chancellor College’, Zomba, Malawi
Hyde Sibande, Ministry of Agriculture, Irrigation and Water Development, Government of Malawi, Lilongwe 3, Malawi
Received: Dec. 14, 2019;       Accepted: Feb. 20, 2020;       Published: Feb. 28, 2020
DOI: 10.11648/j.ajwse.20200601.15      View  173      Downloads  59
Abstract
This study presents the first national-scale assessment of temporal variations in the Base Flow Index (BFI) for watercourses in Malawi. A proxy indicator of groundwater discharge to rivers, the BFI is a measure of the ratio of long term baseflow to total river flow and is a key parameter for sustainable water resources management. The smoothed minima technique was applied to river flow data from 68 river gauges across Malawi (data records ranging from 11-64 years). The long-term average annual BFI for each gauged site was determined, as well as seasonal values of BFI. The Mann Kendal (MK) statistical test was used to identify trends in the BFI. Average annual BFI was 0.57, average wet season BFI was 0.52 and average dry season BFI was 0.97. This indicates that 57%, 52% and 97% of the total river flow is derived from groundwater and other stored sources in the annual, wet and dry season periods respectively. These results show that baseflow in Malawi follows a seasonal pattern with minimal differences between the average annual and average wet season BFI; however, significant increases are generally seen in the dry season BFI. The results also found long-term behavioural changes in BFI across all periods. Annually, 74% showed no trend, 10% showed an increasing trend and 16% showed a decreasing trend. The wet season trends showed similar values with 66% showing no trend, 16% showing an increasing trend and 18% showing a decreasing trend. In contrast, for the dry season, 93% showed no trend, 1% showed an increasing trend and 6% showed a decreasing trend. The dataset determined in this study can support sustainable water resources management in Malawi and contribute to measuring its progress towards Sustainable Development Goal 6.
Keywords
Baseflow, BFI, Groundwater Discharge, Malawi, SDG6
To cite this article
Laura Kelly, Douglas Bertram, Robert Kalin, Cosmo Ngongondo, Hyde Sibande, A National Scale Assessment of Temporal Variations in Groundwater Discharge to Rivers: Malawi, American Journal of Water Science and Engineering. Special Issue: 21st Century Water Management. Vol. 6, No. 1, 2020, pp. 39-49. doi: 10.11648/j.ajwse.20200601.15
Copyright
Copyright © 2020 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Reference
[1]
Singh, S. K.; Pahlow, M.; Booker, D. J.; Shankar, U.; Chamorro, A. Towards baseflow index characterisation at national scale in New Zealand. Journal of Hydrology 2019, 568, 646–657.
[2]
Kelly, L.; Kalin, R. M.; Bertram, D.; Kanjaye, M.; Nkhata, M.; Sibande, H. Quantification of temporal variations in base flow index using sporadic river data: application to the Bua catchment, Malawi. Water 2019, 11, 901.
[3]
World Bank. Assessment of the state of hydrological services n developing countries; 2018.
[4]
Houghton-Carr, H.; Fry, M.; Wallingford, U. The decline of hydrological data collection for the development of integrated water resource management tools in Southern Africa. IAHS publication 2006, 308, 51.
[5]
Tallaksen, L. M.; Van Lanen, H. A. Hydrological drought: processes and estimation methods for streamflow and groundwater; Elsevier, 2004; Vol. 48.
[6]
Bosch, D. D.; Arnold, J. G.; Allen, P. G.; Lim, K.-J.; Park, Y. S. Temporal variations in baseflow for the Little River experimental watershed in South Georgia, USA. Journal of Hydrology: Regional Studies 2017, 10, 110–121.
[7]
Kelly, L.; Bertram, D.; Kalin, R.; Ngongondo, C. Characterization of Groundwater Discharge to Rivers in the Shire River Basin, Malawi. American Journal of Water Science and Engineering 2019, 5, 127–138.
[8]
Brodie, R.; Sundaram, B.; Tottenham, R.; Hostetler, S.; Ransley, T. An adaptive management framework for connected groundwater-surface water resources in Australia. Bureau of Rural Sciences, Canberra 2007.
[9]
International Hydrological Programme of UNESCO. Groundwater Resources Assessment under the Pressures of Humanity and Climate Changes GRAPHIC. 2006.
[10]
Hughes, D. A.; Hannart, P. A desktop model used to provide an initial estimate of the ecological instream flow requirements of rivers in South Africa. Journal of Hydrology 2003, 270, 167–181.
[11]
Beck, H. E.; van Dijk, A. I. J. M.; Miralles, D. G.; de Jeu, R. A.; Bruijnzeel, L. A. (Sampurno); McVicar, T. R.; Schellekens, J. Global patterns in base flow index and recession based on streamflow observations from 3394 catchments. Water Resources Research 2013, 49, 7843–7863.
[12]
Ngongondo, C. S. An analysis of long-term rainfall variability, trends and groundwater availability in the Mulunguzi river catchment area, Zomba mountain, Southern Malawi. Quaternary International 2006, 148, 45–50.
[13]
UNESCO Southern Africa FRIEND IHP-V Project 1.1 Technical Documents in Hydrology No. 15. Paris 1997.
[14]
Kumambala, P. G. Sustainability of water resources development for Malawi with particular emphasis on North and Central Malawi (unpublished PhD thesis), 2010.
[15]
Government of Malawi. National Water Resources Master Plan 2017. Annex 1: Surface Water Resources. 2017.
[16]
Government of Malawi. Water Resources Investment Strategy. Component 1 - Water Resources Assessment. Annex II - Surface Water 2011.
[17]
Fraser, C. M.; Kalin, R. M.; Rivett, M. O.; Nkhata, M.; Kanjaye, M. A national approach to systematic transboundary aquifer assessment and conceptualisation at relevant scales: A Malawi case study. Journal of Hydrology: Regional Studies 2018.
[18]
Government of Malawi. Water Resources Investment Strategy. Component 1 - Water Resources Assessment. Main Report 2011.
[19]
Government of Malawi. Malawi Land Use Map. Forestry Commission 2018.
[20]
Government of Malawi. Malawi Hydrogeological and Water Quality Atlas 2018. Ministry of Agriculture, Irrigation and Water Development 2018.
[21]
Zuzani, P.; Ngongondo, C.; Mwale, F.; Willems, P. Examining trends of hydro-meteorological extremes in the Shire River Basin in Malawi. Physics and Chemistry of the Earth, Parts A/B/C 2019.
[22]
Ngongondo, C.; Xu, C.-Y.; Gottschalk, L.; Alemaw, B. Evaluation of spatial and temporal characteristics of rainfall in Malawi: a case of data scarce region. Theoretical and applied climatology 2011, 106, 79–93.
[23]
Banda, L. C.; Rivett, M. O.; Kalin, R. M.; Zavison, A. S.; Phiri, P.; Kelly, L.; Chavula, G.; Kapachika, C. C.; Nkhata, M.; Kamtukule, S.; others Water-Isotope Capacity Building and Demonstration in a Developing World Context: Isotopic Baseline and Conceptualization of a Lake Malawi Catchment. Water 2019, 11, 2600.
[24]
Institute of Hydrology. Low Flow Studies Report No 3; Institute of Hydrology, Wallingford, UK, 1980.
[25]
Morawietz, M. User’s Guide BFI. Oslo: University of Oslo 1997.
[26]
Mann, H. B. Nonparametric tests against trend. Econometrica: Journal of the Econometric Society 1945, 245–259.
[27]
Kendall, M. G. Rank correlation methods; 4th ed.; Griffin, London, 1975.
[28]
Addinsoft XLSTAT statistical and data analysis solution. Long Island, New York, USA 2019.
[29]
mWater. Technology for Water and Health. https://www.mwater.co/ (accessed Aug 12, 2019).
[30]
Miller, A.; Nhlema, M.; Kumwenda, S.; Mbalame, E.; Uka, Z.; Feighery, J.; Kalin, R. M. Evolving water point mapping to strategic decision making in rural Malawi. 2018.
[31]
Kalin, R. M.; Mwanamveka, J.; Coulson, A. B.; Robertson, D. J.; Clark, H.; Rathjen, J.; Rivett, M. O. Stranded assets as a key concept to guide investment strategies for sustainable development goal 6. Water 2019, 11, 702.
[32]
Truslove, J. P.; VM Miller, A.; Mannix, N.; Nhlema, M.; Rivett, M. O.; Coulson, A. B.; Mleta, P.; Kalin, R. M. Understanding the functionality and burden on decentralised rural water supply: Influence of Millennium Development Goal 7c coverage targets. Water 2019, 11, 494.
[33]
Rivett, M. O.; Miller, A. V.; MacAllister, D. J.; Fallas, A.; Wanangwa, G. J.; Mleta, P.; Phiri, P.; Mannix, N.; Monjerezi, M.; Kalin, R. M. A conceptual model based framework for pragmatic groundwater-quality monitoring network design in the developing world: Application to the Chikwawa District, Malawi. Groundwater for Sustainable Development 2018, 6, 213–226.
[34]
De Graaf, I. E.; Gleeson, T.; van Beek, L. R.; Sutanudjaja, E. H.; Bierkens, M. F. Environmental flow limits to global groundwater pumping. Nature 2019, 574, 90–94.
[35]
Government of Malawi. National Irrigation Master Plan and Investment Framework. Ministry of Agriculture, Irrigation and Water Development 2015.
[36]
Water, U. Integrated Monitoring Guide for Sustainable Development Goal 6 on Water and Sanitation-Targets and global indicators. 2017.
[37]
SDG Tracker Sustainable Development Goals Clean Water and Sanitation https://sdg-tracker.org/water-and-sanitation (accessed 29-11/19).
Browse journals by subject